A list of Android Phones that run AIR?

This is anecdotal, so do keep looking into other numbers, but I helped solved someone's problem recently that may give an indication:

The person in question had a setting wrong, and was asking for devices that have a trackball. When submitting to the marketplace they saw only about 60 devices that could run the app. Once it was fixed, the marketplace said there was over 350 devices.

That seems an incredible amount of devices! No matter how wrong it is, I think you'll have a lot of people who can use your app.